METHOD AND APPARATUS FOR IMPLEMENTING POST-MODULATION ERROR CORRECTION CODING SCHEME

摘要

A method of and apparatus for providing error correction coding for a block of user data in which the user data is initially modulated by a first modulator and then the modulated user data is error correction encoded to produce a first plurality of check bits. The first plurality of check bits are then modulated by a second modulator whose output is then fed to a second error correction encoder which produces a second plurality of check bits. The modulated user data, the first plurality of check bits and the second plurality of check bits are all fed to a shift register where the error correction encoded user data block is formed, useful with magnetic and optical storage devices.